Increasingly more people analyze performance of entities (e.g., machines) using quantitative tools, computer methods, and computer systems. The performance of an entity is frequently expressed as a change in the value of a particular property of an entity over a certain period (e.g., failure rate of machines).
However, with respect to a group of entities (e.g., a group of machines), it is difficult to accurately represent the performance of the group using conventional tools. Therefore, there is a need for a new method and system for analyzing performances of groups of entities.